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Ustilaginales Stock Photos and Images
RMJHM6MF–Corn Smut, North Rhine-Westphalia, Germany / (Ustilago maydis) / Huitlacoche | Maisbeulenbrand, Nordrhein-Westfalen, Deutschland / (Ustilago maydis)
RMKBNR12–Corn cob infected by Corn smut (Ustilago maydis) fungus. It is as well edible and in Mexico considered delicacy.
RMPG4ATE–. Botany for agricultural students . Botany. Fig. 348. — A Bird's Nest Fungus, Nidularia. About natural size. organic matter in the ground. Tlie sporophore is at first globose, but the gleba soon breaks out of the peridium and is elevated to some distance above ground by an elongating stalk. The spore masses arc slimy and have the odor of carrion. Certain insects which dissemi- nate the spores are attracted by the odor. Smuts (Ustilaginales). — The Smuts are parasitic Basidiomycetes. In some Smuts, the mycelium, although evident only in local areas, traverses widely through the host, while in
RMJHM6P7–Corn Smut, North Rhine-Westphalia, Germany / (Ustilago maydis) / Huitlacoche | Maisbeulenbrand, Nordrhein-Westfalen, Deutschland / (Ustilago maydis)
RMKBNR1B–Corn cob infected by Corn smut (Ustilago maydis) fungus. It is as well edible and in Mexico considered delicacy.
RMPG4ATP–. Botany for agricultural students . Botany. 392 THALLOPHYTES. Fig. 348. — A Bird's Nest Fungus, Nidularia. About natural size. organic matter in the ground. Tlie sporophore is at first globose, but the gleba soon breaks out of the peridium and is elevated to some distance above ground by an elongating stalk. The spore masses arc slimy and have the odor of carrion. Certain insects which dissemi- nate the spores are attracted by the odor. Smuts (Ustilaginales). — The Smuts are parasitic Basidiomycetes. In some Smuts, the mycelium, although evident only in local areas, traverses widely through t
RM2AN3TJN–Fungi, Ascomycetes, Ustilaginales, Uredinales . - special characters that, though included under thisheading, they can best be dealt with apart.. 5»=,
RMPG4660–. Farm friends and farm foes : a text-book of agricultural science . Agricultural pests; Beneficial insects; Insect pests. CHAPTER XX The Smut Fungi The Smuts form a distinctive group of parasitic plants called by botanists Ustilaginales. The mycelium develops in the tissues of the host plant and causes serious injury to the parts infested. Spores are developed in the form of the blackish powder so characteristic of Corn Smut and Oats Smut. These primary spores germinate under favor- able conditions and often bring about the development of enormous numbers of secondary spores. Nearly every one
![Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 167. Gymnosporangium davaricuformeRees; germinating teleutospores; x 666.. Fig. 168. a. Phragtnidium violaceumWint., X330; 6. Gymnosporangium clazariaeforme Rees, X260; sper-mogonia; after Blackman. Vlll] UREDINALES 199 Stock Photo](https://c8.alamy.com/comp/2AN32EG/fungi-ascomycetes-ustilaginales-uredinales-fig-167-gymnosporangium-davaricuformerees-germinating-teleutospores-x-666-fig-168-a-phragtnidium-violaceumwint-x330-6-gymnosporangium-clazariaeforme-rees-x260-sper-mogonia-after-blackman-vlll-uredinales-199-2AN32EG.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 167. Gymnosporangium davaricuformeRees; germinating teleutospores; x 666.. Fig. 168. a. Phragtnidium violaceumWint., X330; 6. Gymnosporangium clazariaeforme Rees, X260; sper-mogonia; after Blackman. Vlll] UREDINALES 199 Stock Photo")
RM2AN32EG–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 167. Gymnosporangium davaricuformeRees; germinating teleutospores; x 666.. Fig. 168. a. Phragtnidium violaceumWint., X330; 6. Gymnosporangium clazariaeforme Rees, X260; sper-mogonia; after Blackman. Vlll] UREDINALES 199
RM2AN44FB–Fungi, Ascomycetes, Ustilaginales, Uredinales . uv&f Fig. 7:. Humaria rutilans (Fr.) Sacc; a. telophase of second division in ascus,3370; b. prophase of third division in ascus, showing sixteen curved chromo-somes, < 2N0S..
![Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 95. Balsamia zlilgaris Vitt.; after Tulasne.. Fig. 96. Balsamia vulgarisVitt.; sectionthrough hvmenium ; after Tulasne. Fig. 97. Tuber rufum Pico ; general viewof fertile region; after Tulasne. IV] TUBERALKS 137 Stock Photo](https://c8.alamy.com/comp/2AN3X44/fungi-ascomycetes-ustilaginales-uredinales-fig-95-balsamia-zlilgaris-vitt-after-tulasne-fig-96-balsamia-vulgarisvitt-sectionthrough-hvmenium-after-tulasne-fig-97-tuber-rufum-pico-general-viewof-fertile-region-after-tulasne-iv-tuberalks-137-2AN3X44.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 95. Balsamia zlilgaris Vitt.; after Tulasne.. Fig. 96. Balsamia vulgarisVitt.; sectionthrough hvmenium ; after Tulasne. Fig. 97. Tuber rufum Pico ; general viewof fertile region; after Tulasne. IV] TUBERALKS 137 Stock Photo")
RM2AN3X44–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 95. Balsamia zlilgaris Vitt.; after Tulasne.. Fig. 96. Balsamia vulgarisVitt.; sectionthrough hvmenium ; after Tulasne. Fig. 97. Tuber rufum Pico ; general viewof fertile region; after Tulasne. IV] TUBERALKS 137
RM2AN3129–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 1;.,. Phragmidium violaceum Wint.; migration ofei nil nucleus into fertile cell of caeoma, x 950; alterBlackmail.. Fig. 174. Melampsora Roslrupi Wagn.;paired fertile cells, x 1:00;, afterBlackman and I- u er.
RM2AN352D–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig ifi:. Development of brand-spores ; a. Doassansia Alismalis1 rcs) Corn.; l>. Entyloma Glatuii Dang.; after Dangeard. in pairs in preparation for the formation of the brand-spores. The samestageswere recorded byLutman mDoassansiadeformans,EntylotnaNynipheaeand Urocystis Anemones (fig. 163).
RM2AN4KJR–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 18. Eremasais albus Eidam; a. b. c. d. sexualapparatus; e. /. %. h. fusion of gametangia; *. /!;. development of asci; /. parthenogenetic ascus;x 900-1000; aft ?• Eidam. Ill PLECTASCALES 59. Fig. 19. Ereinascus fertilis Stoppel; stages in the formation of the ascus, both by fusion of twocells and parthenogenetically; after Guilliermond.
RM2AN2R4P–Fungi, Ascomycetes, Ustilaginales, Uredinales . 214 PROTOBASIDIOMYCETES [CH. fertile cells of Phragmidium violaceum was shown by Blackman and subse-quently by Welsford to be derived from one of the smaller cells at the baseof the fertile layer. It is thus a vegetative nucleus; it enters the fertile cellby migrating through the wall, becoming much drawn out and laterally com-pressed. It leaves a pore which maybe identified after its passage (fig. 192)..
![Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 3. Humaria rutilans (Fr.) Sacc; hymenial layershowing asci and paraphyses in various stages of develop-ment, x 400. I.] ASCOMVCETES 37 conditions of moderate dryness, such as occur out of doors on a fine autumnday, by shaking the fructifications, or even by currents of air set up bywalking past them. It can be initiated, as de Bary pointed out, when ripe. Stock Photo](https://c8.alamy.com/comp/2AN4R6G/fungi-ascomycetes-ustilaginales-uredinales-fig-3-humaria-rutilans-fr-sacc-hymenial-layershowing-asci-and-paraphyses-in-various-stages-of-develop-ment-x-400-i-ascomvcetes-37-conditions-of-moderate-dryness-such-as-occur-out-of-doors-on-a-fine-autumnday-by-shaking-the-fructifications-or-even-by-currents-of-air-set-up-bywalking-past-them-it-can-be-initiated-as-de-bary-pointed-out-when-ripe-2AN4R6G.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 3. Humaria rutilans (Fr.) Sacc; hymenial layershowing asci and paraphyses in various stages of develop-ment, x 400. I.] ASCOMVCETES 37 conditions of moderate dryness, such as occur out of doors on a fine autumnday, by shaking the fructifications, or even by currents of air set up bywalking past them. It can be initiated, as de Bary pointed out, when ripe. Stock Photo")
RM2AN4R6G–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 3. Humaria rutilans (Fr.) Sacc; hymenial layershowing asci and paraphyses in various stages of develop-ment, x 400. I.] ASCOMVCETES 37 conditions of moderate dryness, such as occur out of doors on a fine autumnday, by shaking the fructifications, or even by currents of air set up bywalking past them. It can be initiated, as de Bary pointed out, when ripe.
RM2AN398H–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 144. .hiiorpho-FalagriacThaxler; male andfemale individuals,the latter with peri-thecium containing re ; aftei Iter. 12—-2 i8o PYRENOMYCETES [CH. whether exogenous or endogenous, and in the latter case whether producedin simple or compound organs. In this way three families, Peyritschiel-laceae (compound endogenous), Laboulbeniaceae (simple endogenous) andCeratomycetaceae (exogenous) are distinguished.. f ., ?? ?:. ? 9
RM2AN486M–Fungi, Ascomycetes, Ustilaginales, Uredinales . inishes the probability that this isa primitive type, or one that has given riseto cup-shaped forms, and it seems easier tothink of Genea and its allies as derived fromthe Pezizales by the diminution in size ofthe external aperture, the shortening andbroadening of the ascus and the increasedconvolution of the hymenium, than to regardthem as giving rise to that group by thecontrary changes. It is, however, not impro-bable that the Pezizales are polyphyletic inorigin, and that some of them may have beenderived from the higher Geoglossaceae. So far
RM2AN4DYM–Fungi, Ascomycetes, Ustilaginales, Uredinales . iphaceaeand Perisporiaceae show severalpoints in common both with thePlectascales, from which theydiffer in the regular arrangementof their asci, and with the Pyre-nomvcctes, from which they arefor the most part distinguishedby the absence of an ostiole. Their taxonomic position isprobably somewhere betweenthese two groups, and they have,under various systems of classifi-cation, been placed in closer proxi-mity sometimes to the one andsometimes to the other. Their in-clusion here in the Plectomycetesis due to the fact that they, orrather their be
RM2AN2T8J–Fungi, Ascomycetes, Ustilaginales, Uredinales . succeededin recognizing several separatechromosomes; a similar stateof affairs has been recorded byChristman for Phragmidiumspeciosum so that it would ap-pear that the different speciesof rusts are at dissimilar levelsin this matter, though a furtherstudy of carefully fixed materialmight be undertaken with ad-vantage. In all cases, however, thedivisions of the fusion nucleusof the teleutospore are muchmore elaborate than those in thevegetative cells and show someof the characteristics of a meioticIn Coleosporium (fig. 189) the fusion nucleus at f
![Fungi, Ascomycetes, Ustilaginales, Uredinales . he cell. All attempts to bring about the germination v] HYPOCREALES ?47 of these spermatia have failed, and no relation of any kind has been de-monstrated between them and the female organ, consequently they must be inled as no longer functional, and their original use can be inferred onlyfrom their structure. Their small size, scanty contents, and large nucleussuggest that they are more appropriately constituted to act as fertilizingi i 111s than as a means of vegetative propagation. The archicarp first appears as a multinucleate hypha, which be Stock Photo](https://c8.alamy.com/comp/2AN3R1D/fungi-ascomycetes-ustilaginales-uredinales-he-cell-all-attempts-to-bring-about-the-germination-v-hypocreales-47-of-these-spermatia-have-failed-and-no-relation-of-any-kind-has-been-de-monstrated-between-them-and-the-female-organ-consequently-they-must-be-inled-as-no-longer-functional-and-their-original-use-can-be-inferred-onlyfrom-their-structure-their-small-size-scanty-contents-and-large-nucleussuggest-that-they-are-more-appropriately-constituted-to-act-as-fertilizingi-i-111s-than-as-a-means-of-vegetative-propagation-the-archicarp-first-appears-as-a-multinucleate-hypha-which-be-2AN3R1D.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . he cell. All attempts to bring about the germination v] HYPOCREALES ?47 of these spermatia have failed, and no relation of any kind has been de-monstrated between them and the female organ, consequently they must be inled as no longer functional, and their original use can be inferred onlyfrom their structure. Their small size, scanty contents, and large nucleussuggest that they are more appropriately constituted to act as fertilizingi i 111s than as a means of vegetative propagation. The archicarp first appears as a multinucleate hypha, which be Stock Photo")
RM2AN3R1D–Fungi, Ascomycetes, Ustilaginales, Uredinales . he cell. All attempts to bring about the germination v] HYPOCREALES ?47 of these spermatia have failed, and no relation of any kind has been de-monstrated between them and the female organ, consequently they must be inled as no longer functional, and their original use can be inferred onlyfrom their structure. Their small size, scanty contents, and large nucleussuggest that they are more appropriately constituted to act as fertilizingi i 111s than as a means of vegetative propagation. The archicarp first appears as a multinucleate hypha, which be
RM2AN3XHX–Fungi, Ascomycetes, Ustilaginales, Uredinales . rincipal modificationsbeing in the direction of adaptation to subterranean conditions by increasedprotection of the hymenium. This appears to have been achieved either byretaining the closed form of the young pezizaceous apothecium {Genea,Pachyphloeus) or by invagination of the fertile layer {Tuber) over a widelyexposed surface such as is found in R/iiziua or Sphaerosoma. In eithercase room has been made foradditional asci by throwing thehymenium into elaboratefolds.Massee, however, regards theglobose asci and dark-colouredsculptured spores of Tu
RM2AN3EWY–Fungi, Ascomycetes, Ustilaginales, Uredinales . . ? Fig. 124. Xyiaria HypoxylonGtev., after Tulasne.woven and rising vertically from the surface of the substratum. As theygrow the stromata assume their characteristic shape, conidia appear anddrops of pinkish or yellowish fluid are exuded. When these dry up, blackdots indicating the position of the ripening perithecia are seen. 168 PYRENOMYCETES [en.. Fig. i 2 5. Porottia pitnc/ala (L.) Fr.; rt. surface, ^. lateral view;after Tulasne.
RM2AN4CR1–Fungi, Ascomycetes, Ustilaginales, Uredinales . s able to recognize an antheridium and oogonium and theformation of an ascus or asci from the latter. These and several subsequentinvestigations have rendered the reproductive processes in the Erysiphaceaebetter known than perhaps in any other group of fungi. Spliaerotlieca Humuli* occurs on a variety of common plants, on thecultivated strawberry, where it is responsible for strawberry mildew,and especially on the hop. On the latter it is widely distributed inautumn, and, if the female inflorescences are infected, may do considerabledamage. The m
RM2AN3PM7–Fungi, Ascomycetes, Ustilaginales, Uredinales . ationof a vegetative and a female nucleus. The binucleate character of the later formed large cells may, as hesuggests, be due to conjugate division, but, since he finds that the numerousbinucleate cells in the sheath1 are the result of rapid growth, this characterin the large cells is evidently susceptible of the same explanation. In anycase the rest of the archicarp degenerates and owing to the refractorycharacter of the material the ascogenous hyphae could not be further traced. According to Blackman and Welsford, all the cells of the archicar
RM2AN39KN–Fungi, Ascomycetes, Ustilaginales, Uredinales . the oogonial and the upperof the trichophoric nucleus. These divide simultaneouslyand a binucleate inferior sterile cell is separated from thebinucleate fertile cell. This in turn divides to form theascogenic cells, from which the asci are to develop, andthese and the asci which they produce are thereforebinucleate. The two nuclei in the ascus fuse and theirunion is regarded by Faull as the only nuclear fusionwhich occurs in this very curious life history. Meiosisthen takes place, followed by the third division. Theupper daughter nuclei of this d
RM2AN4EG1–Fungi, Ascomycetes, Ustilaginales, Uredinales . s hyphaeramify. Erom the penultimatecells of the latter binucleateasci aredeveloped,and afterthenuclei have fused eight sporesare formed. The ascus wallbreaks down and the spores arefinally set free after the decayof the outer layer of the sheath. This sheath, with the en-closed mass of free ascospores,was long regarded as a singleorgan containing an indefinitenumber of spores; for thisreason the fungus was placedin the Hemiasci and given the Fi<generic name of Monascus.The later stages of develop-ment are in fact difficult tofollow and have b
RM2AN30W7–Fungi, Ascomycetes, Ustilaginales, Uredinales . lf ruptured and exposes the ripe spores. It becomes torn andrecurved so that the characteristic cluster-cup is produced (fig. 176). Thepseudoperidium is sometimes much elongated and cylindrical or inflated,producing the forms known as roestelia (Gymnosporangium), and peri-dermium (Coleosporium, Cronartium and allied genera), so-called from theirold generic names, or it may be represented only by a few paraphyses oraltogether absent (Phragmidium, Melampsord). The latter forms, to whichthe term caeoma is applied, are probably primitive. In the majo
RM2AN3GKG–Fungi, Ascomycetes, Ustilaginales, Uredinales . hemost part on seed plants but in some cases on Pteridophyta, Bryophyta orLichens. The perithecia are immersed in the substratum, the ostiole onlyprojecting, but they may become more or less exposed by the rupture of thecovering tissues. The peridium is leathery or membranous. The genus Pleospora includes some 225 species, several of which occuron grains and other grasses where they show biological specialization.Pleospora kerbarum is a facultative parasite on the leaves of angiosperms ;the perithecium is initiated by the division of a hypha into
RM2AN45W6–Fungi, Ascomycetes, Ustilaginales, Uredinales . er extremities of the vegetative hyphae are the young paraphyses.Their number is constantly increased by the pushing in of new branchesfrom below, and thus the conical outline of the mass is maintained. Theascogenous hyphae grow for a certain distance in company with thevegetative filaments, then their upward growth ceases, and they spread out horizontally, forming a rather dense layerbelow the cone of paraphyses. This is thebase of the hymenium. Usually in Pyronema, as in Ascodesmis,several oogonia are invested by a commonsheath, and their ascog
RM2AN357T–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig 161. Tilletia Tritici (Bjerk) Wint.;a. basidium ihirly hours after germination1 if brand-spore; /. conjugation of basidio-spores : ? .,oo: after Plowright. 194 HEMIBASIDIOMYCETES [ch. pairs of associated nuclei takes place. Rawitscher observed a quite similarlife-history in T. lacvis. In the parasitic mycelium of Doassansia Alismatis and Entyloma Glaucii(fig. 162) Dangeard observed binucleate cells and the fusion of their nuclei.
RM2AN4301–Fungi, Ascomycetes, Ustilaginales, Uredinales . of its cells and in the amount oftwisting which it undergoes. The central oogonial region includes three to seven large cells withgranular contents. Between this and the parent hypha is a stalk of variablelength and beyond it is a terminal portion (or trichogyne) of not more thanseven cells which are narrower than the rest and appear to degenerate early(Cutting). The cells come into communication with one another by large pores (fig.8ia), and Cutting has shown thatnuclear fusions (fig. Si£)take placein all the cells of the oogonialregion, and tha
RM2AN325Y–Fungi, Ascomycetes, Ustilaginales, Uredinales . the suggestion was long ago made that theymay be male reproductive elements, and this is borne out by their largenuclei and lack of reserve material, and is by no means invalidated by thefact that they possess some slight power of germination. Recent investigationhas shown that they are now no longer functional. As a rule considerable numbers of spermatia are to be found in variousstages of degeneration scattered around the ostioles of the spermogonia.In some cases the spermatia are aggregated in sticky masses and appearto attract insects. The pr
RM2AN2WDE–Fungi, Ascomycetes, Ustilaginales, Uredinales . ll, they have no opportunity of dissolving partnershipand the influences which bring about meiosis affect both alike. A considerable similarity exists in the arrangement of the differentgroups of sporogenous cells. The uredo- and teleutosori are clearly com-parable, both are of indefinite extent, with or without a border of paraphyses,and both consist of groups of rectangular basal cells from which the sporemother-cells arise in horizontal series and divide to produce the simple orcompound spore and the stalk-cell. Sometimes, however, the uredosp
RM2AN462X–Fungi, Ascomycetes, Ustilaginales, Uredinales . that an exceedinglystrong ring unites the antheridium and trichogyne, and they can be bentor turned upon each other without being pulled apart. This arrangementis no doubt necessary to withstand the strain set up by the flow of nucleifrom the relatively wide cavity of the antheridium through the narrow poreand beak. IV I PEZIZALES 105 While the formation of the pore is in progress the nuclei of the tricho-gyne degenerate, and, by the time that they are completely disorganized, a migration of the male nuclei through the pore begins. Ultimately the
RM2AN46JC–Fungi, Ascomycetes, Ustilaginales, Uredinales . t from the same mycelium. Both aremultinucleate from their initiation. Very soon a slight elevation appears on the oogonium; it elongatesrapidly to form the multinucleate trichogyne and, before its growth iscomplete, is separated from the oogonium by a wall; the trichogyne andantheridium grow towards one another, the tip of the trichogyne meetingsometimes the apex, but more commonly the flank of the male organ. The mature oogonium is a spherical or flask-shaped cell filled withdense-cytoplasm and containing many nuclei which are very much largert
RM2AN32PY–Fungi, Ascomycetes, Ustilaginales, Uredinales . as a local stimulant causing more or less markedhypertrophy and consequent curling or malformation of the infected part.Starch may be stored by the host, and this is so abundant in the hyper-trophies caused by the aecidial mycelium of Puccinia Caricis on the nettle,Urtica parvifolia, that they are eaten by the Himalayans; one or two otherspecies are similarly employed. Where the mycelium penetrates into theperennial tissues of the host it is itself perennial. Spores and Sori. On the mycelium several kinds of spore are produced,minute spermatia in
RM2AN3N58–Fungi, Ascomycetes, Ustilaginales, Uredinales . n the ordinary vegetative mycelium, conidia areproduced. An ostiole is lacking in (//. fitnete, presumably the most primitivemember of the genus; in the remaining species it is present and the peri-thecium is of the typical sphaeriaceous form. In Chaetomium spirale the cells of the mycelium contain each a singlenucleus, the archicarp arises as a coiled branch and divides into four ormore uninucleate cells. There is no sign of an antheridium. Vegetativehyphae grow up from the stalk of the archicarp, and from the filament onwhich it is borne, and f
RM2AN4MJ5–Fungi, Ascomycetes, Ustilaginales, Uredinales . nterpretation,if found, as pathological phenomena; (2) the recognition of as manychromosomes in the third division inthe ascus as in the first; (3) the observation of paired nucleiin the ascogenous hyphae. The first of these grounds has a mainly negative value; in regard tothe second, further investigation is very much to be desired; the statementof the chromosome number without figures is of little value, nor is anyfigure of the third division significant except that of the late anaphase; in theearlier stages chromosomes are scattered about the
RM2AN2TH0–Fungi, Ascomycetes, Ustilaginales, Uredinales . ear and fourbasidiosporcs are produced, which, in due course, give rise to a uninucleatemycelium. The sporophytic stage thus endures only from the fusion of thefertile cells until the germination of the spores which they produce. Incidentally these observations in the case of Kunkelia nitens havedemonstrated that the caeoma of this fungus is not a stage in the life-historyof the teleutospore-producing Puccinia Peckiana on the same host, for themycelial cells of/. Peckiana are binucleate and the teleutospores germinatein the usual way. The develop
RM2AN4E64–Fungi, Ascomycetes, Ustilaginales, Uredinales . ruitis subterranean. The species differ from the other hypogeal Ascomycetes,the Tuberales, with which they are still sometimes classified, and resemblethe subaerial Plectascales in the irregular arrangement of their asci, whichare scattered or grouped in nests surrounded by sterile branches (fig. 57). Thegleba or central complex of hyphae is not at any stage of development incommunication with the exterior. In the Elaphomycetaceae the ascocarp is surrounded by a thick yellowor brown peridium, the asci are subglobose and the gleba breaks up atmatu
RM2AN40GE–Fungi, Ascomycetes, Ustilaginales, Uredinales . centre, infecting one plant after another and causing them to lose theirneedles and die. The mycelium ramifies in the intercellular spaces ofthe cortex, and within as well as between the cells of the bast, so that thesieve-tubes are completely filled. It forms also masses of pseudoparenchymabetween the dead and diseased tissues of the host. The development of the ascocarp has been studied in R. undnlata whereFitzpatrick found a long, multicellular archicarp recalling that of some ofthe Ascobolaceae. He regards the terminal cell or cells as a tric
RM2AN2YWT–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig- 77- PucciniaFalcariae; branchedfertile cell of aecidium or primaryuredosorus, x 1200: after Dittschlag. Fig. 1 ;*. Phragmidium Potcntillae-CanadensisDiet.; a. conjugation; /. branched fertilecell; after Christman. 204 PROTOBASIDIOMYCETES [CH. But the fact that these sori are developed on the same mycelium as thespermogonia, the fact that in their fertile cells nuclear association takesplace and the fact that in the formation of the fertile cell a sterile cell is cutoff, all suggest that the true homology is with the aecidium. The mycelium fo
RM2AN3TW1–Fungi, Ascomycetes, Ustilaginales, Uredinales . gina-tions of the upper surface, and internally the loose tissue of the sterile veins1 01 nes recognizable. Owing to the rapid growth of the upper portion of the young fruit, thebasal sheath is bent backwards, while at various points along the fertile veinsthe first signs of asci appear. Later the peripheral tissues become thickened,together with the remains of the basal sheath, and form the peridium. Thisultimately closes over the points where the fertile veins are in communicationwith the exterior. Thus the young fruit is open at first, the hym
RM2AN47PC–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 55. Sepultaria coron M uniseriate spores ; ascus opening bya lid; branched, septate, clavateparaphyses; x 600. 7 98 DISCOMYCETES [ch. should be ultimately established, the curious stalked conidium of Ascoboluscarbonarius. The archicarp is of much commoner occurrence, and seems more likelyto be useful as a gauge of relationship. Among Discomycetes the simplesttype is undoubtedly that of Ascodesmis or Thelcbolus; the significant detailsin Thelebohis are not fully known, but in Ascodesmis we have a stout, twistedhypha, divided into three parts,
RM2AN478C–Fungi, Ascomycetes, Ustilaginales, Uredinales . becomes wrapped (fig. 60 d). In the meantime walls are laiddown, so that the various archicarpsand antheridia become cut off fromtheir neighbours, and each archicarpdivides transversely to form a tri-chogvne and an oogonium. The trichogyne usually contains two nuclei,the oogonium five or six and the antheridium about the same number. Thenuclei of the trichogyne soon degenerate, and, as observed by Claussen, thewall between this cell and the antheridium is broken down (fig. 60e), sothat open communication is established. The male nuclei pass into
RM2AN4N0W–Fungi, Ascomycetes, Ustilaginales, Uredinales . J ASCOMYCETES 45 was proposed. The occurrence of ;i brachymeiotic reduction has since beenobserved in several other fungi, and has also been in several cases denied. Chromosome Association. There are a number of fungi, of whichPhyllactinia Corylea is perhaps the most fully studied, in which no change inthe chromosome number takes placethroughout the life-history. In Phyl-lactinia, Harper showed in 1905 thatthe chromosomes remain visible instrands attached to the central bodythroughout the resting stages. Ineach of the nuclei of the developingascu
RM2AN3FT0–Fungi, Ascomycetes, Ustilaginales, Uredinales . inite extent in which the perithecia are completely immersed ; the ascuscontains eight spores in contrast to the numerous spores of certain species ofCalosphaeria and of Diatrypclla, a genus further distinguished by the cushion-shaped stroma. Xylariaceae The Xylariaceae occur chiefly on wood; they represent the highestdevelopment of the Sphaeriales and are characterized by the free superficialstroma which is only very rarely, as in Hypoxylon, partly sunk in the sub-stratum, and shows every variety of form from a spreading crust on thesurface of t
RM2AN3AJY–Fungi, Ascomycetes, Ustilaginales, Uredinales . bviously corresponds to the cell in which fertilization isnow known to occur in other Ascomycetes and will therefore here be termedthe oogonium. In Stigmatomyces Baeri the trichogyne is simple (fig. 1^6 d, e) but inmany other members of the group it undergoes frequent septation andbranches freely. The apices of the branches are alone receptive and maystraight or spirally coiled (fig. 137). However elaborate, the trichogyne quicklydisappears, collapsing and breaking off as soon as its function is fulfilled. In endogenous species the sperms are sho
RM2AN3CEB–Fungi, Ascomycetes, Ustilaginales, Uredinales . -celled, attached to the integument of the host bya blackened base or foot. From the receptacle grow out filamentous appen-dages on or among which the male organs are produced and, with a few-exceptions, the receptacle of the same individual also gives rise to a femaleorgan fr< im which a perithecium liberating ascospores is eventually developed. The plant is covered by a thin, homogeneous membrane which is ex-ceedingly tough and impervious and is developed from the gelatinous coatof the spore; it efficiently protects the cells from desiccatio
RM2AN35CH–Fungi, Ascomycetes, Ustilaginales, Uredinales . -spore of T. Tritici the nucleus passesinto the basidium and divides three times so that eight nuclei are formed.Eight basidiospores are budded off in abunch at the apex of the basidium, andeach receives a single nucleus. Frequentlyadditional nuclear divisions take placeand ten, twelve, or sixteen uninucleatespores may be produced. When the sporesare fully formed short conjugating tubesgrow out and connect neighbouringspi nes, often while these are still attachedto the basidium (fig. 161). According to Rawitschcr the nucleusof one cell of the pai
RM2AN4BDW–Fungi, Ascomycetes, Ustilaginales, Uredinales . ; the rest, as a rule, are uninucleate. Just after fertilization the sheath begins to grow up (fig. 44 o), springingin this case from the stalk cell of the antheridium, as well as from that ofthe oogonium, and developing into the three layers described above. The ascogenous hyphae arise as lateral branches from the septateoogonium (fig. 44 c), all or most being derived from the penultimate cellabout which they are crowded and intertwined. They are at first multi-nucleate, and, as development proceeds, push up vertically within the peri-thecium (f
RM2AN4JMC–Fungi, Ascomycetes, Ustilaginales, Uredinales . -products varies during the progress of fermentationand according to external conditions. In particular, fermentation is affei tedby the presence or absence of free oxygen. Under conditions of plentifulaeration the yeast grows and multiplies rapidly and much of the sugar isused as food; under anaerobic conditions, on the other hand, the main partof the sugar is utilized in respiration, alcoholic fermentation is more complete.unl the quantity of alcohol produced is greater in proportion to the numberof cells concerned. On the ground that their dau
RM2AN3DG7–Fungi, Ascomycetes, Ustilaginales, Uredinales . rther investigation, especially from thispoint of view. In both Xylaria and Hypoxylon the young stroma is covered by a tangle 170 PYRENOMYCETES [CH. of conidiophores, from which small oval conidia are abstricted. In Xylariathese form a white coating, in marked contrast to the older black portionsof the stroma, where the perithecia are maturing, and justify the namecandle-snuff fungus, applied to some of the commoner species. If, in eithergenus, the stroma be sectioned during the conidial stage, nests of smallhyphae, similar to those in Poronia, w
RM2AN3BEX–Fungi, Ascomycetes, Ustilaginales, Uredinales . 133). One or more appendages are borne on the receptacle. These are moreor less filamentous and often elaborately branched. They bear the maleorgans and serve also lor the protection of the delicate trichogyne and perhapsfacilitate fertilization by holding a drop of water around the organs con-cerned. The primary appendage is developed from the upper segment ofthe germinating spore and is terminal; the later formed secondary append-ages, when present, are outgrowths from the cells of the receptacle. The male element is a non-motile cell which as
RM2AN3KC4–Fungi, Ascomycetes, Ustilaginales, Uredinales . estion nor the development of the perithecium has yetbeen elucidated. A mphisphaeriaceae In the Amphisphaeriaceae the young perithecium is sunk in the substra-tum; as it matures it becomes more or less free, though in contrast to the con-dition in the Sphaeriaceae and Ceratostomataceae, its base is always immersed. Development has been studied in a species of Teichospora and a species ofTeichosporella, now both included under the genus Strickeria, charac-terized by its muriform spores.The spore produces numerousgerm-tubes which give rise to amyce
RM2AN31P9–Fungi, Ascomycetes, Ustilaginales, Uredinales . fertile layer isdifferentiated. In PucciniaPoarittn nuclear migrationssometimes take place be-tween the vegetative cellsat the base of the veryyoung aecidium. Thesecells may grow up, eitherat once or after division, toform fertile cells. The aecidiospores, then,are the products of asexualprocess by means of whichtwo nuclei become associated within thelimits of a single protoplasmic mass, form-ing the dikaryon or synkaryon of Maire.The nuclei thus brought together do notfuse, but undergo simultaneous division(fig. 174), so that a daughter nucleus,
RM2AN4RGK–Fungi, Ascomycetes, Ustilaginales, Uredinales . her by an irregular tear or by dehiscencealong a definite line, and the spores are shot out in a jet of liquid while thedeflated ascus sinks back to about half its size (figs. 4, 5). In forms with anexplosive mechanism the ascus often elongates considerably during the latterpart of its development; the spores are arranged at the upper end and eitherfloat suspended in the fluid contents of the ascus, or are attached to theapex and to one another by cytoplasmic strands (Sordaria, Podospora,fig. 2 e). The explosive ejection of spores from different
RM2AN4G0M–Fungi, Ascomycetes, Ustilaginales, Uredinales . ans of Eurotium herbariorum weredescribed by de Bary in his classical researches of 1870. He distinguisheda coiled, septate archicarp, and saw that its tip fused with a comparativelystraight antheridial hypha, the membranes between breaking down, and herecognized that from it the asci are ultimately derived. More recently it has been shown that the archicarp of Eurotium ismade up of three parts: a multicellular stalk, a unicellular oogonium, anda unicellular trichogyne. In E. herbariorum these parts may be clearlydistinguished (fig. 30^), but the
![Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 6. Sort/aria sp.; ascocarp in longitudinal sectionshowing asci, paraphyses and periphyses; X400. II] ASCOMYCETES 39 e-. hymenium. In Desmotascus1, a pyrenomycetous fungus parasitic on Bromelia,the paraphyses are replaced by a thin-walled pseudoparenchyma recallingthe arrangement in the higher Plectomycetes. The Peridium. The peridium or wall of the ascocarp is a weft of sterilehyphae in which the individualfilamcntsare sometimes clear-ly distinguished, sometimesclosely interwoven to form apseudoparenchyma; the wallsof the outer cells are so Stock Photo](https://c8.alamy.com/comp/2AN4P3M/fungi-ascomycetes-ustilaginales-uredinales-fig-6-sortaria-sp-ascocarp-in-longitudinal-sectionshowing-asci-paraphyses-and-periphyses-x400-ii-ascomycetes-39-e-hymenium-in-desmotascus1-a-pyrenomycetous-fungus-parasitic-on-bromeliathe-paraphyses-are-replaced-by-a-thin-walled-pseudoparenchyma-recallingthe-arrangement-in-the-higher-plectomycetes-the-peridium-the-peridium-or-wall-of-the-ascocarp-is-a-weft-of-sterilehyphae-in-which-the-individualfilamcntsare-sometimes-clear-ly-distinguished-sometimesclosely-interwoven-to-form-apseudoparenchyma-the-wallsof-the-outer-cells-are-so-2AN4P3M.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 6. Sort/aria sp.; ascocarp in longitudinal sectionshowing asci, paraphyses and periphyses; X400. II] ASCOMYCETES 39 e-. hymenium. In Desmotascus1, a pyrenomycetous fungus parasitic on Bromelia,the paraphyses are replaced by a thin-walled pseudoparenchyma recallingthe arrangement in the higher Plectomycetes. The Peridium. The peridium or wall of the ascocarp is a weft of sterilehyphae in which the individualfilamcntsare sometimes clear-ly distinguished, sometimesclosely interwoven to form apseudoparenchyma; the wallsof the outer cells are so Stock Photo")
RM2AN4P3M–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 6. Sort/aria sp.; ascocarp in longitudinal sectionshowing asci, paraphyses and periphyses; X400. II] ASCOMYCETES 39 e-. hymenium. In Desmotascus1, a pyrenomycetous fungus parasitic on Bromelia,the paraphyses are replaced by a thin-walled pseudoparenchyma recallingthe arrangement in the higher Plectomycetes. The Peridium. The peridium or wall of the ascocarp is a weft of sterilehyphae in which the individualfilamcntsare sometimes clear-ly distinguished, sometimesclosely interwoven to form apseudoparenchyma; the wallsof the outer cells are so
RM2AN4M53–Fungi, Ascomycetes, Ustilaginales, Uredinales . The Significance of the Fusion in the Ascus. If this be the case itremains to consider the significance of the fusion in the ascus. The presenceof more than one nucleus in this cell, destined to be one of the largest inthe life-cycle of the fungus, is hardly surprising especially in coenocyticforms. In uninucleate species it forms part, as Harper pointed out in 1905,of the quantitative adjustment frequently observed between cytoplasm andnuclear material. But this nucleo-cytoplasmic relation does not explain whyfusion should take place between the
RM2AN3RTK–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 10:. Polystigma rtibrumTiQ,.; maturearchicarp, x Koo; after Blackmail andWelsford.. Fig. 103. Xylaria polymorfha (Pers.) Crev.archicarp embedded in stroma, x 1000. readily be derived from the first. It occurs in forms where the perithecium isimmersed either in the substratum or in a stroma, and its essential characteris the prolongation of the tip of the archicarp to form a trichogyne-like01 an. The appearance of this structure is associated with the developmentofspermatia in spermogonia. Archicarps of the type in question are foundin Polyst
RM2AN4D3C–Fungi, Ascomycetes, Ustilaginales, Uredinales . s genusalso the apex of the perithecium is furnished with a ring of richly branchedpenicillate cells. At about the time of spore-formation these break down,forming a sticky gelatinous cap, by means of which the perithecium, afterit is first set free, adheres upside down to its original host plant or to otherobjects. In view of this peculiarity the ascription of Phyllactinia to anyhost in contact with which its perithecia may be found demands careful veri-fication. The function of the true appendages in the Erysiphaceae is somewhatvariable. In Phy
RM2AN3P4D–Fungi, Ascomycetes, Ustilaginales, Uredinales . pharmacopoeia, but from its rarity only usedby the Emperors physician. The striking belief that it is a herb insummer and a worm in winter, may perhaps sufficiently account for theesteem in which it was held. Tin ascospores are multicellular and filiform and when shed break upinto their separate cells. Germ-tubes from these, or from the conidia, infectthe insect either as a caterpillar or chrysalis, and penetrating into its interiorgive rise to cylindrical conidia which enter the blood-stream and increaseby east-like budding till the insect die
RM2AN35K3–Fungi, Ascomycetes, Ustilaginales, Uredinales . lei approach oneanother and fuse to form the single nucleus of the spore. < rermination in water takes place in the usual way; four-celled basidiaare produced and give rise to basidi< ispi res. Among these there is no evidenceof conjugation. Ustilago antkerarum forms its spores in the stamens of members of the Caryophyllaceae; pollen-formation is inhibited, and the anthers become filled with fungal spores, which are distributed by the mechanism prepared for the persal of the pollen. Germination takes place in dung decoction with great readi
RM2AN45NA–Fungi, Ascomycetes, Ustilaginales, Uredinales . Lachnea stercorea is a small orange species occurring during the winterand spring on the dung of various animals, especially of cows. WithHumaria graimlata and Ascobolus furfuraceus, it is among the very commoncoprophilous forms, appearing in many parts of Britain with great regularitywhen the Piloboli have died down, and the cow pad is beginning to dry.It is about 4 mm. in diameter and is furnished with numerous stout, septatehairs. The archicarp arises as a side branch from the vegetative mycelium, anddivides to form four or more cells. The ter
RM2AN424N–Fungi, Ascomycetes, Ustilaginales, Uredinales . he formation of a single fruit. These, it would appear, areall borne upon the same hypha ; they may arise from adjacent cells, andindeed sometimes open into one another, so that the whole series seemsequivalent to the oogonial region of A. carneus. Each cell, however, isdescribed as bearing a twisted, multicellular trichogyne, which would indicatethat each is an independent organ. Large ascogenous hyphae arise from theseveral oogonia, and the view suggests itself that the so-called trichogynemay be in fact a premature ascogenous hypha. It is, at
RM2AN4A9Y–Fungi, Ascomycetes, Ustilaginales, Uredinales . of the stone. Infection apparently takes place at about the time of the opening of thebuds of the host, probably by means of spores deposited on the bud-scales;in cold, moist weather, when the young leaves are in a state of loweredvitality, the fungus readily gains entrance; it can be checked by the use ofappropriate sprays. Once in the leaf the hyphae in most cases ramifybetween the cells of the host, but in Taphrinopsis Laurencia on Pterisbiaurita they are intracellular. No haustoria are developed. The mycelium may be annual or it may be perenn
RM2AN45F1–Fungi, Ascomycetes, Ustilaginales, Uredinales . a. mature ascocarp, xoo; b. <? development of archicarp,X300; d. older archicarp showing crowded nuclei, x 400 ; e mature archicarp withelaborately branched trichogyne, x 400;/. three ascogonial cells united by very largepores, X400. to ascogenous hyphae. Thus the oogonial region, though developmentallymulticellular, is for all practical purposes unicellular at maturity, and offersno greater difficulties in the way of fertilization than the oogonium ofPyroncma itself. The branched character of the trichogyne is exceptional among Disco-mycetes
RM2AN3W4J–Fungi, Ascomycetes, Ustilaginales, Uredinales . *•£&& Bucholtz was able to examine, showed a system of internal chambers linedby the hymenium and communi-cating at one or more points withthe exterior. As development pro-ceeds these cavities increase in sizeand the hymenium becomes furtherconvoluted,so that additional cham-bers are formed. In Tuber the ascocarp is ir-regularly globose, fleshy or some-times almost woody; internally thewalls which divide the gleba areextensively branched, and the freespace between them is diminished,so that the layers of the hymeniumare brought close together and
RM2AN35WY–Fungi, Ascomycetes, Ustilaginales, Uredinales . Zea Mays, induces con-siderable hypertrophy. Thedeformations contain a massof gelatinous mycelium from which brand-spores are produced. Whenmature, the spore mass causes the rupture of the enclosing tissues, and thespores escape. They germinate to produce basidia from which uninucleatebasidiospores are abstricted. These in turn multiply by budding, but, accord-ing to Rawitscher, they never conjugate, nor do they form a definite mycelium(fig. i$6a). In the infection of the host plant, hyphae are for the first timedeveloped, and, unlike those of mo
RM2AN2XTT–Fungi, Ascomycetes, Ustilaginales, Uredinales . its wall is variously roughened in most speciesby minute projections on the surface. Two or more germ-pores are usuallypresent and the uredospore, like the cells which give rise to it, is invariablybinucleate ; it produces a binucleate mycelium on which teleutospores orfurther crops of uredospores are formed. Certain species(Puccinia vexans,etc),occurring under very dry conditions, lit I LRKDINALKS 205 produce a second type of uredospore with thick walls which arc adapted tosurvive unfavourable conditions; these are known as amphispores. Both a
RM2AN3RA5–Fungi, Ascomycetes, Ustilaginales, Uredinales . siphales and Laboulbeniales, and in view of thelongitudinal divisions, perhaps especially to the latter. In Neciria the usually red or yellow perithecia are produced in groups onstromata of the same colour; the asci contain eight ascospores which are two-celled, and often produce conidia by budding while still in the ascus. Thegenus is large, including some 250 species among which .V. cinnabarina, thecommonest in this country, is of very frequent occurrence on the living anddead branches of deciduous trees. The mycelium from the germinatingspores
RM2AN4T0T–Fungi, Ascomycetes, Ustilaginales, Uredinales . e ascospore may beregarded as undergoing premature germination. Divisions may take placein three dimensions, so that the spore is muriform (fig. 1), or the septa maybe all in one plane so that it consists of a row of cells (fig. 2 a). The multicellular spore thus produced may break up into its constituentcells, which proceed with their development independently, or it may functionas a single structure. In examining any of these characters or in measuring the size of thespore it is essential to deal with fully mature examples since the distinctive
RM2AN46AF–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 62. Pyromma conjluens; a. antheridium, trichogyne and oogonium,male and female nuclei collected in the middle of the latter; b. c. fusionof male and female nuclei; after Harper. spread out into the cytoplasm of the beak, suggesting that the solventaction is mainly exerted from the interior of the trichogyne. The openpore now becomes thickened around its margin so that an exceedinglystrong ring unites the antheridium and trichogyne, and they can be bentor turned upon each other without being pulled apart. This arrangementis no doubt necessary
RM2AN43XW–Fungi, Ascomycetes, Ustilaginales, Uredinales . th it by meansof pores (fig. j6 b). Additional nuclei pass into it from both the stalk andterminal cells, and Welsford has observed their fusion in pairs in theoogonium. The fusion nuclei pass into the ascogenous hyphae. The asciare large and produce each eight spores which are violet or brownish incolour; the epispore is characteristically sculptured at maturity. There areeight chromosomes in the first division in the ascus, and four in the secondand third (Dangeard (fig. 13), Fraser and Brooks). In Ascobolus glaber the archicarp is larger and m
RM2AN43E6–Fungi, Ascomycetes, Ustilaginales, Uredinales . of the ascusthe number of chromosomes is stated by Ramlow to be sixteen through-out, but he does not figure the essential third anaphase. Ascobolus ccuiwnarius occurs on burnt ground among charcoal. Theascocarp is scurfy (furfuraceous), and greenish, or later brownish in colour.Numerous conidia are formed on the mycelium, and, according to Dodge,it is from a conidium, germinating while still attached to its stalk, that thearchicarp is produced. It consists of a multicellular stalk, a fertile portionwhich contains twenty to fort) cells arranged in
RM2AN48WY–Fungi, Ascomycetes, Ustilaginales, Uredinales . etative, some ascogenous. Thesegive rise to the sub-hymenial layer where the paraphyses have their originand where the young asci are developed. The asci and paraphyses grow uptogether and rise to the surface of the ascocarp forming the hymenium orfertile disc which is spread over the interior of the cup. The asci are moreor less cylindrical and parallel one to another and to the paraphyses (fig. 53).They open either by a lid (fig. 55) or by the ejection of a plui; (fig. 54).They arise in succession so that large numbers may be produced in a sing
RM2AN48CR–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 53. Hiimaria rutilans (Kr.) Sacc.; hymenial layershowing asci and paraphyses in various stages of develop-ment, x 400. Fig.54. Mitrulalaricina Mass*; development and ejection ofbiseriate spores, x 600. This typically discomycetous ascocarp orapothecium, which is well seenin the Pezizales, may be connected in one direction, through the Patel-lariaceae and their allies, with the fructifications of the Phacidiales, which areparti}- closed with a more or less stellate aperture, and with the characteristic-ally elongated fructifications of the Hy
RM2AN4PE4–Fungi, Ascomycetes, Ustilaginales, Uredinales . )- ex-posed (fig. 7). To the closedor flask-shaped forms theterm perithecium is ap-plied, the cup and its vari-ants are known as apo-thecia. Inthe simplerasco-carps the asci are irregu-larly scattered; in the apo-thecia and flask-shaped perithecia they are regularly arranged, forming amore or less parallel series and intermingled with paraphyses. The Paraphyses. The paraphyses of the Ascomycetes are slender hairs,of about the same length as the asci; they usually develop earlier than thelatter, and have a protective and possibly a nutritive funct
![Fungi, Ascomycetes, Ustilaginales, Uredinales . uninvesti-gated. They have a fleshy or waxy disc, pale and clear coloured, usuallywhite, yellow, or tinged with pink. The sheath is not always developed, whenpresent it is thin and white and is mealy owing to the presence of particles IV] 1IIAC IDIALHS 133 of calcium oxalate; when the fruit opens it forms a white border around thehymenium. The pale colour, and the ragged or toothed dehiscence of thesheath are very characteristic. Phacidiaceae The Phacidiaceae are distinguished by their black, thick-walled apothecia,usually scattered, sometimes, a Stock Photo](https://c8.alamy.com/comp/2AN3XYR/fungi-ascomycetes-ustilaginales-uredinales-uninvesti-gated-they-have-a-fleshy-or-waxy-disc-pale-and-clear-coloured-usuallywhite-yellow-or-tinged-with-pink-the-sheath-is-not-always-developed-whenpresent-it-is-thin-and-white-and-is-mealy-owing-to-the-presence-of-particles-iv-1iiac-idialhs-133-of-calcium-oxalate-when-the-fruit-opens-it-forms-a-white-border-around-thehymenium-the-pale-colour-and-the-ragged-or-toothed-dehiscence-of-thesheath-are-very-characteristic-phacidiaceae-the-phacidiaceae-are-distinguished-by-their-black-thick-walled-apotheciausually-scattered-sometimes-a-2AN3XYR.jpg "Fungi, Ascomycetes, Ustilaginales, Uredinales . uninvesti-gated. They have a fleshy or waxy disc, pale and clear coloured, usuallywhite, yellow, or tinged with pink. The sheath is not always developed, whenpresent it is thin and white and is mealy owing to the presence of particles IV] 1IIAC IDIALHS 133 of calcium oxalate; when the fruit opens it forms a white border around thehymenium. The pale colour, and the ragged or toothed dehiscence of thesheath are very characteristic. Phacidiaceae The Phacidiaceae are distinguished by their black, thick-walled apothecia,usually scattered, sometimes, a Stock Photo")
RM2AN3XYR–Fungi, Ascomycetes, Ustilaginales, Uredinales . uninvesti-gated. They have a fleshy or waxy disc, pale and clear coloured, usuallywhite, yellow, or tinged with pink. The sheath is not always developed, whenpresent it is thin and white and is mealy owing to the presence of particles IV] 1IIAC IDIALHS 133 of calcium oxalate; when the fruit opens it forms a white border around thehymenium. The pale colour, and the ragged or toothed dehiscence of thesheath are very characteristic. Phacidiaceae The Phacidiaceae are distinguished by their black, thick-walled apothecia,usually scattered, sometimes, a
RM2AN38BB–Fungi, Ascomycetes, Ustilaginales, Uredinales . and blisters, often as largeas a fist, on the stem, leaves, roots, andespecially the flowers of Zca Mays;and Urocystis F/o/rt^deforms the stemsand leaves of various species of Viola.Several other smuts develop theirspores in the ovary of the host plant, orinfect the stamens, filling the antherswith spores and benefiting by themeans of distribution provided for thepollen. Ustilago antherarttm^ eveninduces development in the staminalrudiments of the normally pistillateflowers of Lychnis dioica. The stamensformed undergo dehiscence as usualand diffe
RM2AN2RHG–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig. 190. Gymnosporangium clavariaeforme Reesfirst division in basidium, x [460; after Blackman.. 214 PROTOBASIDIOMYCETES [CH. fertile cells of Phragmidium violaceum was shown by Blackman and subse-quently by Welsford to be derived from one of the smaller cells at the baseof the fertile layer. It is thus a vegetative nucleus; it enters the fertile cellby migrating through the wall, becoming much drawn out and laterally com-pressed. It leaves a pore which maybe identified after its passage (fig. 192).
RM2AN4DP7–Fungi, Ascomycetes, Ustilaginales, Uredinales . ofconsiderable thickness. The Erysiphaceae are propagated during the summer by rather largeoval uninucleate conidia (fig. 38). These are ordinarily produced in rows on simple conidiophores with one ormore basal cells. In the endophyticE. taurica, however, the conidia areborne singly on branched conidio-phores which emerge through thestomata of the host. In the case ofPhyllactinia Cory-lea, which is met with on a largenumber of deciduous trees, variationsoccur in the shape of the conidiaborne on different hosts, and indicatethe existence of morpho
RM2AN3MK0–Fungi, Ascomycetes, Ustilaginales, Uredinales . is continued so that a mass of cells is pro-duced from which asci at last arise. In the meantime the sheath becomesdifferentiated into an outer coat of relatively large, brown-walled hyphae,and an inner layer of smaller cells which become narrow and elongated. Asdevelopment proceeds a cavity appears within the perithecium, usually justabove the ascogenous cells, and branches from the lining mycelium grow out to form the periphyses; paraphysesare not produced (fig. 114). The ripe spores are shed into thecavity of the perithecium, and do notreach t
RM2AN31WT–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fig Uromyces Poae Raben.; young aecidium,? 370; after Blackmail and Fraser. Puccinia Poarum (Blackmail and Fraser 06), Puccinia Falcariae (Ditt-schlag 10)), or directly below the epidermis (Phragmiditim violacaim (Black-man 04), Uromyces Poae (Blackman and Fraser 06) (fig. 171), PucciniaClaytoniata (Fromrne 14)); these hyphae give rise to a more or less regularseries of uninucleate cells. These are the fertile cells, but, before developingfurther, each, at any rate in the relatively primitive forms (caeomata), maycut off one or occasionally more
RM2AN4095–Fungi, Ascomycetes, Ustilaginales, Uredinales . tends. Development has been studied only in species of Helvetia where thefruit arises as a tuft of branching, septate hyphae, and no archicarp hasbeen observed. In //. elastiea, young ascophores, about 05 mm. in diameter, show nosigns of fertile hyphae. A membrane of interwoven filaments encloses thewhole fruit body, and below this a palisade of club-shaped hyphae is differ-entiated. As growth proceeds the membrane becomes broken, and thepalisade increases in regularity, forming the boundary of the fructificationexcept where, at the apex, the par
RM2AN4B5R–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fg- 45- Phyllactinia Corylea (Pers.) Karst.; peri-thecium containing uninucleate asci;after Harper. Fig. 46. Phyllactinia Corylea(Pers.) Karst.; a. b. fusion inascus; after Harper. Eight chromosomes (fig. 47) have been observed throughout the life-history. In Phyllactinia Corylea and also in Microsphaera AIni(Sands, 1907) andvarious species of Erysiphe (Harper, 1905), the organization of the restingnucleus is very characteristic. A deeply staining central body lies againstthe nuclear membrane and to this the chromatin threads are attached.From it
RM2AN4AN2–Fungi, Ascomycetes, Ustilaginales, Uredinales . Fg- 45- Phyllactinia Corylea (Pers.) Karst.; peri-thecium containing uninucleate asci;after Harper. Fig. 46. Phyllactinia Corylea(Pers.) Karst.; a. b. fusion inascus; after Harper. Eight chromosomes (fig. 47) have been observed throughout the life-history. In Phyllactinia Corylea and also in Microsphaera AIni(Sands, 1907) andvarious species of Erysiphe (Harper, 1905), the organization of the restingnucleus is very characteristic. A deeply staining central body lies againstthe nuclear membrane and to this the chromatin threads are attached.From it
RM2AN4HGW–Fungi, Ascomycetes, Ustilaginales, Uredinales . in Emericella the sheath opens by a pore,but in the majority of cases it remains closed, and the ascospores are finally Ill ll.KCTASCALES 69 liberated by its decay. The asci arc spherical or pyriform and contain twot eight continuous spores, the walls of which may be variously ornamented.In both Penicillium and Eurotium the perithecium may develop an excep-tionally thick wall, and pass into a resting stage sometimes several weeksin duration. Such a structure is described as a sclerotium. In Eurotium herbariorutn* the development of perithecia is
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